The Logical Structure of Arguments(WA Chapter 4)

CS4001

Kristin Marsicano

Formal vs. Real-World logic What is the difference? What is the role of assumptions?

Formal vs. Real-World logic What is the difference?

Formal logic “if all ps are qs, and if r is a p, then r is a q” represents something provable

Real-world logic

Not so cut and dry; we want to know the particulars on a case-by-case basis

Difficult to say rs are always ps, or that every instance of p results in q

What is the role of assumptions? Real-world arguments are not grounded in abstract, universal

statements; instead must be grounded in believes, assumptions, or values granted by the audience beliefs, assumptions, or values are often unstated! Note, if the underlying

assumptions aren’t shared, the writer has a problem (they must defend the assumption)

Formal vs. Real-World Logic In your term paper, which will you be

dealing with?

Formal vs. Real-World Logic In your term paper, which will you be

dealing with? Real-world logic, which is why we avoid using

the word “prove” your paper is not meant to prove anything instead, it’s meant to make a good case – to weaken the

resolve of those who resist your claim or strengthen the resolve of those who agree

Who is Stephen Toulmin?

Who is Toulmin? Stephen Toulmin British philosopher 1950s - Rejected model of argument based on

formal logic Developed an alternate model to analyzing/developing arguments

Toulmin Model: Assumptions Audience-based courtroom model Assumes:

All assertions and assumptions are contestable by an “opposing council” (as in court)

Verdicts will be rendered by a neutral (3rd) party (the judge, the jury, or (in your case) the reader)

Framing the argument with the courtroom in mind helps you think about reasons for both supporting and opposing your case

Toulmin Model: Key Terms Claim Reason Enthymeme Grounds Warrant Backing Rebuttal

Recall: Definition of Argument

Recall: Definition of Argument A claim supported by a reason, usually stated

as a because clause

Enthymeme What is it? Give an example; outline the unstated

underlying assumption

Enthymeme What is it?

incomplete logical structure claim and reason that depends on on unstated

assumptions To serve as a starting point for the argument,

underlying assumptions should be a belief, value, or principle shared by the audience

Give an example (from WA ch. 4:) “The public school should not support marine

parks and “swim with dolphins” programs because these programs separate dolphins from their natural and social groups”

Assumption: Wild animals should remain free in their natural habitats and social groups

Enthymeme Exercise Given each of the following enthymemes,

identify the unstated assumption the audience must supply in order to make the enthymeme persuasive. Dogs make good pets because they are loyal. We shouldn’t elect Joe as a committee chair

because he is too bossy. Drugs should not be legalized because legalization

would greatly increase the number of drug addicts.

We need laws to control the sale of guns because so many innocent people are getting killed.

Warrant

Warrant Underlying assumption that turns an

enthymeme into a complete, logical structure Value, belief, or principle that audience has to

hold if the soundness of the the argument is to be guaranteed

Grounds

Grounds “What grounds do you have to support your

claim?” E.g. “the grounds for divorce” Should answer “how do you know that…”

Evidence supporting the claim’s reason Facts, data, statistics, causal links, testimony,

examples, anecdotes, etc.

Backing

Backing Argument that supports the warrant Must be introduced when the warrant itself is

not convincing enough to the audience

BackingExample:“Affirmative Action is a necessary initiative to help

minorities achieve equality in education and employment.”

What is the warrant (underlying assumption)?

BackingExample:“Affirmative Action is a necessary initiative to help

minorities achieve equality in education and employment.”

What is the warrant (underlying assumption)?- Equality should be achieved, but is has not been

already

What if your reader believe that minorities have already achieved equality in education and employment? How could you convince them otherwise?

Rebuttal What are the two main front on which

someone could rebut your argument?

Rebuttal What are the two main front on which

someone could rebut your argument? Reasons or grounds Warrants or backings

To strengthen your argument, acknowledge and address: that there are limitations on your claim that you are aware of the opposing point of view

Qualifier

Qualifier Expresses author’s degree of certainty

concerning the claim (limit force of claim, indicate degree of probable truth)

Very likely, probably, maybe, except for, etc..

Putting it all together: Applying Toulmin We can apply the Toulmin Schema to analyze

another person’s argument, or to build our own!

I recommend you try this exercise when constructing the argument for your term paper.

The Importance of Audience-Based Reasons “Whenever you ask whether a given piece of

writing is persuasive, the immediate rejoinder should always be, ‘Persuasive to whom?’”

Consider our friend Gordon Adams (remember him?)

Applying Toulmin to Gordon’s Argument Enthemyme:

Claim: Reason: Grounds:

Warrant: Backing:

Who was Gordon’s audience? How did the warrant relate to that audience? How might he have have created a more persuasive argument?

Putting it all together: Applying Toulmin Example provided from book:

Dolphins Bossy Joe Drugs